New Industry Products

AEC-Q100 Linear LED Driver-Controller Features Enhanced Dimming

July 02, 2019 by Scott McMahan

Diodes Incorporated announced the AL5814Q, an automotive-compliant linear LED driver-controller with low dropout voltage and open LED detection for automotive linear-driven LED lamps.

The AL5814Q is suitable for automotive applications demanding specific change control, and it is AEC-Q100 qualified. It has a grade 1 temperature rating, is PPAP capable, and it is manufactured in IATF16949:2016 certified facilities.

The device operates from an input voltage in the range of 4.5V to 60V. It has up to 15mA drive and uses an external drive transistor, MOSFET or BJTs, minimizing its power dissipation.

This ability to drive multiple LED strings or higher current LEDs makes it suitable for applications that require higher light output such as rear lamps, license plate illumination, instrument panels, and internal lamps.

The AL5814Q's VSET pin can be utilized to adjust the output current feedback level for a lower dropout via resistor divider, analog dimming and thermal fold-back. Analog dimming is implemented using an NTC resistor.

PWM dimming is supported with the application of a PWM signal to the VFAULT pin. Over-temperature protection is also included, along with input under-voltage lockout. Open-LED detection, via the VFAULT pin, can also be supported with its activation through the SFAULT pin.

If VFAULT is brought lower than 2.5V (as a result of any one of the multiple LED channels going open), the AL5814Q's output goes low turning off the external transistors. The device recovers when the open condition is removed.

This ability of VFAULT to turn off the external transistors also allows PWM dimming of the LED current by adding PWM control signal on VFAULT pin.

The AL5814Q's tight 0.4V reference voltage (±5% across temperature) offers a high level of thermal stability and matching between lamps.


  • Qualified to AEC-Q100 Grade 1
  • Wide Input Voltage Range from 4.5V to 60V
  • Configurable LED Current Setting
  • 5% Reference Voltage Tolerance Across Operating Temperature
  • Low Temperature Drift
  • 15mA Output Drive Capability for MOSFET or Bipolar Transistor
  • LED Open Protection Detected by VFAULT Pin
  • PWM Dimming Realized Through VFAULT Pin
  • LED Thermal Foldback Configured by VSET
  • Overtemperature Protection (OTP)
  • Input Undervoltage Lockout

AL5814Q is available in the exposed MSOP-8EP package, and it is priced at $0.25 each in 1000 piece quantities.